Heretofore, ascorbic acid has been used as an antiscurvy drug. It is also known that ascorbic acid is involved in collagenation and inhibits production of melanins in the body. Recently, it has been reported that this substance has anticancer activity as well. On the other hand, glycyrrhetic acid is known to have antiinflammatory activity. However, neither of these compounds is satisfactory enough in efficacies.
Therefore, the inventors of the present invention searched for new more active compounds and found, as a consequence, that a novel compound corresponding to ascorbic acid and glycyrrhetic acid linked together through a phosphoric acid residue meets the above object. The present invention has been conceived and developed on the basis of the above finding.